“Have you ever tried to chase a rainbow?”. Maybe sometimes, you have seen a rainbow after the rain and run towards it, hoping to touch it or find the “foot of the rainbow”. But no matter where you run, the rainbow is always… far away. Like a magical secret that the sky does not want to reveal. So, today, I-CLC will answer a very familiar question that few people really understand.<\/span><\/i><\/p>\n C\u1ea7u v\u1ed3ng \u0111\u01b0\u1ee3c h\u00ecnh th\u00e0nh t\u1eeb \u00e1nh s\u00e1ng m\u1eb7t tr\u1eddi\u00a0<\/b><\/p>\n Rainbows are formed from sunlight.<\/i><\/b><\/p>\n B\u00e9 c\u00f3 th\u1ec3 nh\u00ecn \u00e1nh s\u00e1ng M\u1eb7t Tr\u1eddi tr\u00f4ng c\u00f3 v\u1ebb tr\u1eafng, nh\u01b0ng th\u1ef1c ra l\u00e0 s\u1ef1 k\u1ebft h\u1ee3p c\u1ee7a nhi\u1ec1u m\u00e0u \u2013 \u0111\u1ecf, cam, v\u00e0ng, l\u1ee5c, lam, ch\u00e0m, t\u00edm. Th\u1ef1c ch\u1ea5t c\u1ea7u v\u1ed3ng kh\u00f4ng xu\u1ea5t hi\u1ec7n m\u1ed9t c\u00e1ch ng\u1eabu nhi\u00ean, m\u00e0 \u0111\u00f3 l\u00e0 k\u1ebft qu\u1ea3 c\u1ee7a m\u1ed9t s\u1ef1 t\u01b0\u01a1ng t\u00e1c tuy\u1ec7t \u0111\u1eb9p gi\u1eefa \u00e1nh s\u00e1ng M\u1eb7t Tr\u1eddi v\u00e0 c\u00e1c gi\u1ecdt n\u01b0\u1edbc nh\u1ecf trong kh\u00f4ng kh\u00ed. Sau c\u01a1n m\u01b0a,\u00a0 kh\u00f4ng kh\u00ed v\u1eabn c\u00f2n \u0111\u1ea7y nh\u1eefng gi\u1ecdt n\u01b0\u1edbc li ti. Khi \u00e1nh s\u00e1ng M\u1eb7t Tr\u1eddi xuy\u00ean qua ch\u00fang, m\u1ed9t hi\u1ec7n t\u01b0\u1ee3ng k\u1ef3 di\u1ec7u x\u1ea3y ra – kh\u00fac x\u1ea1 \u00e1nh s\u00e1ng.”Kh\u00fac x\u1ea1 \u00e1nh s\u00e1ng” \u2013 n\u00f3i n\u00f4m na, d\u1ec5 hi\u1ec3u \u2013 l\u00e0 hi\u1ec7n t\u01b0\u1ee3ng \u00e1nh s\u00e1ng b\u1ecb b\u1ebb cong khi \u0111i t\u1eeb m\u00f4i tr\u01b0\u1eddng n\u00e0y sang m\u00f4i tr\u01b0\u1eddng kh\u00e1c, t\u1ee9c l\u00e0 \u00e1nh s\u00e1ng s\u1ebd \u0111\u1ed5i h\u01b0\u1edbng \u0111i qua hai m\u00f4i tr\u01b0\u1eddng kh\u00e1c nhau: kh\u00f4ng kh\u00ed v\u00e0 n\u01b0\u1edbc. I-CLC \u0111\u01b0a ra v\u00ed d\u1ee5 cho b\u00e9 d\u1ec5 h\u00ecnh dung h\u01a1n nh\u00e9: khi b\u00e9 th\u1ea3 m\u1ed9t <\/span>c\u00e1i mu\u1ed7ng v\u00e0o ly n\u01b0\u1edbc<\/b>, v\u00e0 quan s\u00e1t t\u1eeb b\u00ean ngo\u00e0i, b\u00e9 th\u1ea5y <\/span>mu\u1ed7ng b\u1ecb cong ho\u1eb7c l\u1ec7ch<\/b> \u0111\u00fang kh\u00f4ng? \u0110\u00f3 ch\u00ednh l\u00e0 do <\/span>\u00e1nh s\u00e1ng b\u1ecb kh\u00fac x\u1ea1<\/b> khi \u0111i t\u1eeb n\u01b0\u1edbc ra kh\u00f4ng kh\u00ed, l\u00e0m h\u00ecnh \u1ea3nh <\/span>b\u1ecb l\u1ec7ch \u0111i<\/b>.<\/span><\/p>\n Sunlight may look white to you, but it is actually a combination of many colors – red, orange, yellow, green, blue, indigo, violet. In fact, rainbows do not appear randomly, but are the result of a beautiful interaction between sunlight and tiny water droplets in the air. After a rain, the air is still full of tiny water droplets. When sunlight passes through them, a magical phenomenon occurs – refraction of light. “Refraction of light” – simply put, easy to understand – is the phenomenon of light being bent when passing from one medium to another, that is, light will change direction when passing through two different mediums: air and water. I-CLC gives an example for you to visualize more easily: when you drop a spoon into a glass of water, and observe from the outside, do y see the spoon bent or crooked? That is because light is refracted when passing from water to air, causing the image to be distorted.<\/span><\/i><\/p>\n Quay l\u1ea1i hi\u1ec7n t\u01b0\u1ee3ng kh\u00fac x\u1ea1 \u00e1nh s\u00e1ng \u1edf c\u1ea7u v\u1ed3ng nh\u00e9. \u0110\u1ea7u ti\u00ean, \u00e1nh s\u00e1ng s\u1ebd <\/span>b\u1ecb b\u1ebb cong<\/b> (hay c\u00f2n g\u1ecdi l\u00e0 kh\u00fac x\u1ea1) khi \u0111i v\u00e0o gi\u1ecdt n\u01b0\u1edbc. Sau \u0111\u00f3, n\u00f3 <\/span>b\u1ecb ph\u1ea3n x\u1ea1<\/b> b\u00ean trong, r\u1ed3i l\u1ea1i <\/span>b\u1ecb b\u1ebb cong th\u00eam l\u1ea7n n\u1eefa<\/b> khi tho\u00e1t ra ngo\u00e0i. Qu\u00e1 tr\u00ecnh n\u00e0y \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 <\/span>kh\u00fac x\u1ea1, ph\u1ea3n x\u1ea1 v\u00e0 t\u00e1n s\u1eafc<\/b>.Trong qu\u00e1 tr\u00ecnh \u0111\u00f3, \u00e1nh s\u00e1ng tr\u1eafng b\u1ecb <\/span>chia t\u00e1ch th\u00e0nh c\u00e1c m\u00e0u kh\u00e1c nhau<\/b>, v\u00e0 \u0111\u00f3 ch\u00ednh l\u00e0 \u0111i\u1ec1u ch\u00fang ta nh\u00ecn th\u1ea5y: m\u1ed9t d\u1ea3i c\u1ea7u v\u1ed3ng lung linh tr\u1ea3i d\u00e0i tr\u00ean b\u1ea7u tr\u1eddi.<\/span><\/p>\n \u00a0Back to the phenomenon of light refraction in a rainbow. First, the light is bent (or refracted) as it enters the water droplet. Then it is reflected inside, and then bent again as it exits. This process is called refraction, reflection, and dispersion. During this process, white light is split into different colors, and that is what we see: a shimmering rainbow stretching across the sky.<\/span><\/i><\/p>\n C\u1ea7u v\u1ed3ng kh\u00f4ng ph\u1ea3i l\u00e0 m\u1ed9t \u201cv\u1eadt th\u1ec3\u201d \u2013 \u0111\u00f3 l\u00e0 hi\u1ec7u \u1ee9ng \u00e1nh s\u00e1ng<\/b><\/p>\n A rainbow is not a \u201cthing\u201d \u2013 it\u2019s a light effect<\/i><\/b><\/p>\n Ti\u1ebft l\u1ed9 m\u1ed9t b\u00ed m\u1eadt cho b\u00e9 nh\u00e9, c\u1ea7u v\u1ed3ng m\u00e0 c\u00e1c b\u00e9 nh\u00ecn th\u1ea5y, c\u1ee9 ng\u1ee1 \u0111\u1ebfn \u0111\u1ee7 g\u1ea7n th\u00ec s\u1ebd ch\u1ea1m v\u00e0o – kh\u00f4ng ph\u1ea3i m\u1ed9t th\u1ef1c th\u1ec3 c\u00f3 th\u1ec3 ch\u1ea1m v\u00e0o \u0111\u01b0\u1ee3c nh\u01b0 cu\u1ed1n v\u1edf, c\u00e2y b\u00fat,..m\u00e0 th\u1ef1c ch\u1ea5t ch\u1ec9 l\u00e0 m\u1ed9t hi\u1ec7u \u1ee9ng \u00e1nh s\u00e1ng m\u00e0 th\u00f4i. N\u00ean b\u00e9 \u0111\u1eebng c\u1ed1 t\u00ecm ki\u1ebfm \u0111i\u1ec1u g\u1ecdi l\u00e0 \u201cch\u00e2n c\u1ea7u v\u1ed3ng\u201d nh\u00e9, v\u00ec s\u1ebd kh\u00f4ng t\u00ecm th\u1ea5y ho\u1eb7c ch\u1ea1m v\u00e0o \u0111\u00e2u nh\u00e9. Th\u1ee9 \u00e1nh s\u00e1ng nhi\u1ec1u m\u00e0u n\u00e0y l\u00e0 m\u1ed9t <\/span>\u1ea3o \u1ea3nh \u00e1nh s\u00e1ng<\/b>, ch\u1ec9 xu\u1ea5t hi\u1ec7n khi m\u1eaft nh\u00ecn th\u1ea5y \u00e1nh s\u00e1ng b\u1ecb t\u00e1n x\u1ea1 \u1edf m\u1ed9t g\u00f3c nh\u1ea5t \u0111\u1ecbnh. M\u1ed9t g\u00f3c l\u00ed t\u01b0\u1edfng \u0111\u1ec3 ng\u1eafm hi\u1ec7n t\u01b0\u1ee3ng quang h\u1ecdc tuy\u1ec7t \u0111\u1eb9p n\u00e0y l\u00e0 g\u00f3c <\/span>42 \u0111\u1ed9<\/b>. Ch\u00ednh v\u00ec v\u1eady, c\u00e1c b\u00e9 th\u1ef1c ra \u0111ang nh\u00ecn th\u1ea5y m\u1ed9t <\/span>c\u1ea7u v\u1ed3ng “ri\u00eang”<\/b> c\u1ee7a m\u00ecnh, t\u00f9y thu\u1ed9c v\u00e0o v\u1ecb tr\u00ed \u0111ang \u0111\u1ee9ng. Khi b\u00e9 di chuy\u1ec3n, g\u00f3c nh\u00ecn thay \u0111\u1ed5i \u2013 v\u00e0 <\/span>c\u1ea7u v\u1ed3ng c\u0169ng “di chuy\u1ec3n” <\/b>theo b\u00e9. \u0110\u00f3 l\u00e0 l\u00fd do t\u1ea1i sao ch\u00fang ta <\/span>kh\u00f4ng th\u1ec3 n\u00e0o ch\u1ea1m v\u00e0o \u0111\u01b0\u1ee3c n\u00f3<\/b>.<\/span><\/p>\n Let me tell you a secret, the rainbow that you see, and think that when you get close enough, you will touch it – is not a tangible entity like a notebook, a pen, etc., but is actually just a light effect. So don’t try to look for the so-called “rainbow foot”, because you won’t find it or touch it. This multi-colored light is a <\/span><\/i>light illusion<\/i><\/b>, which only appears when the eye sees light scattered at a certain angle. An ideal angle to see this beautiful optical phenomenon is an angle of <\/span><\/i>42 degrees<\/i><\/b>. Therefore, you are actually seeing your own <\/span><\/i>“private” rainbow<\/i><\/b>, depending on where you are standing. When you move, the viewing angle changes – and<\/span><\/i> the rainbow also “moves”<\/i><\/b> with you. That’s why we <\/span><\/i>can’t touch it<\/i><\/b>.<\/span><\/i><\/p>\n![\"\"](\"https:\/\/i-clc.edu.vn\/wp-content\/uploads\/2025\/05\/2.jpg\")
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